NEW "iSpy" technology is set to give parents a window into their children's Facebook activity, with instant alerts provided when children stray into dangerous territory.

The cybersafety service, available from today, aims to catch out bullies and predators before the damage is done.

Its developers also hope it will get parents and children talking about the dangers of the web, with new research showing two in five parents now keep tabs on their teens without their consent.

The Telstra Safe Social tool scans social network sites such as Facebook, Twitter, YouTube and MySpace on any device.

SMS and email alerts can be sent as soon as concerning behaviour such as abusive or offensive words, inappropriate content and friend requests from strangers is detected. The danger list is updated daily.

Activity can also be monitored via a screen "dashboard" or with daily or weekly reports.

Telstra safety expert Darren Kane said the Cloud-based technology should be seen as a way for children to prove they could be trusted online.

"We're not saying this is a silver bullet," Mr Kane said. "But we are saying that it is a product that may help."

AVG Technologies research showed 41 per cent of Australian parents used Facebook to keep tabs on their teenagers without their consent.

A similar number worried their children could ruin future job prospects by inappropriate internet use, 22 per cent feared their kids were sexting and more than a quarter had seen abusive or explicit comments on their children's accounts.

Dr John Lenarcic, a lecturer at Melbourne's RMIT University, said there was a risk children could create duplicate social media accounts to avoid being monitored.

They must hand parents their log-ins for Telstra's system to work.

"I think a lot of these issues can be solved through education rather than almost policing behaviour, which is what this is," Dr Lenarcic said.

Other companies had similar services but this was likely to be popular because it was from a well-known company, he said.

Father-of-three Don Robinson, who allows only his eldest son, Josh, to use Facebook, said a monitoring service could be helpful.

"Sometimes they think it's a closed world and they're just having a chat with their mates, but everyone can see what they've said," Mr Robinson said.

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